1. Field of the Invention
This invention relates to a method for re-using expanded styrene by processing used expanded styrene to fabricate regenerated products, and an apparatus used in this method for processing expanded styrene.
2. Description of the Related Art
Expanded styrene is superior in shock-absorption, heat-insulating and heat retaining properties, and hence is used extensively for packaging a wide variety of products from electric appliances to food and beverages.
However, this expanded styrene has a drawback that it presents disposal difficulties when the articles are unpacked and the packaging material is to be discarded. That is, expanded styrene, which has become unnecessary, was simply destroyed or incinerated. However, this disposal system is now to be re-considered because of the problems of procurement of land-filling sites and public hazards caused by bad smell or smoke generated on incineration.
In order to meet this request, there has been proposed a processing apparatus for expanded styrene such as is disclosed in Japanese Laying-Open Patent H-1-89110 or in Japanese Laying-Open Patent H-6-166034. The processing apparatus pulverizes the unneeded expanded styrene, transports the pulverized product on a belt conveyor and illuminates far-ultra-red light from a far-ultra-red heater provided partway on the transport path to reduce its volume. If the far-ultra-red light is illuminated to heat the pulverized product of the expanded styrene, as in this processing apparatus for the expanded styrene, the used styrene can be reduced in its volume without causing fusion decomposition or bad smell or elevating the furnace temperature. Thus, the processing apparatus for expanded styrene is meritorious in handling the unneeded expanded styrene as a waste material.
However, if the expanded styrene is processed using the above-described processing apparatus, the aforementioned problem cannot be solved completely because the expanded styrene, reduced in its volume on pulverization, is handled as a waste material.
It is therefore desired to re-use the pulverized expanded styrene, thus reduced in its volume, as a starting material for producing a regenerated product. However, the pulverized expanded styrene, thus reduced in its volume, is not uniform in size and shape, such that it cannot be used as a starting material for injection molding.
It is therefore an object of the present invention to provide a method for re-using unneeded used expanded styrene and a processing apparatus for expanded styrene for producing pulverized expanded styrene.
In one aspect, the present invention provides a method for re-using expanded styrene including a first step of comminuting expanded styrene, a second step of illuminating far-infra-red light to the expanded styrene comminuted by the first step to reduce the volume thereof, a third step of further comminuting expanded styrene, reduced in volume by the second step, to prepare a granulated material and a fourth step of injection-molding the granulated material from the third step to prepare a regenerated article.
In this re-using method for expanded styrene, unneeded expanded styrene is first-order comminuted in the first step to a pre-set size. The expanded styrene, first-order comminuted in the first step, is illuminated by far-infra-red light in the second step and thereby reduced in volume.
The expanded styrene, reduced in volume by the second step, is second-order comminuted in the third step to a granulated material having uniform size and shape. The granulated material from the third step is injection-molded in the fourth step to produce a regenerated article. This enables the unneeded expanded styrene to be re-used as a starting material for a regenerated article.
In another aspect, the present invention provides an apparatus for processing expanded styrene including first comminuting means for first-order comminuting charged expanded styrene, heating means for heating and reducing the volume of the expanded styrene first-order comminuted by the first comminuting means by illuminating the far-infra-red light thereon and second comminuting means for first-order comminuting the expanded styrene reduced in volume by the heating means to prepare a granulated material.
The first comminuting means first-order comminutes the unneeded expanded styrene to a pre-set size. The expanded styrene, first-order comminuted by the first comminuting means, is routed to the heating means.
The heating means illuminates the far-infra-red light on the expanded styrene, first-order comminuted by the first comminuting means, to heat the expanded styrene to reduce its volume. The expanded styrene, reduced in volume by this heating means, is sent to the second comminuting means.
The second comminuting means second-order comminutes the expanded styrene, first-order comminuted by the heating means, to render the expanded styrene uniform in size and shape to prepare a granulated starting material.
The granulated starting material, prepared by this processing apparatus for expanded styrene, is charged into, for example, an injection molding machine so as to be used as a starting material for a regenerated article as the product of the injection molding machine.
In the re-using method for the expanded styrene according to the present invention, unneeded expanded styrene is comminuted in the first step to the comminuted expanded styrene which is illuminated in the second step by the far-infra-red light and thereby reduced in volume. The expanded styrene, thus reduced in volume, is further comminuted in the third step to give a granulated starting material which is injection-molded in the fourth step to produce a regenerated article. Thus, the unneeded expanded styrene can be re-used without producing pollution problems attributable to increased volume of industrial wastes and disposal thereof on incineration.
Moreover, the processing apparatus for expanded styrene according to the present invention is configured for first-order comminuting unneeded expanded styrene by the first comminution means, illuminating the far-infra-red light by heating means to reduce its volume and second-order comminuting the material reduced in volume by second-order comminuting means to prepare the granulated starting material. This gives a re-usable starting material uniform in size and shape.
Therefore, if the unneeded expanded styrene is processed using the processing apparatus for expanded styrene according to the present invention, the expanded styrene, which is not needed, can be used as a starting material for a regenerated article, without handling the unneeded expanded styrene as a waste material, thus completely eliminating the pollution of other problems attributable to increased volume of the industrial wastes or disposal thereof on incineration.
Moreover, since the present processing apparatus for expanded styrene illuminates the far-infra-red light on the unneeded expanded styrene for reducing its volume without causing decomposition on fusion, it is possible to prevent bad smell or smoke of combustion attributable to decomposition on fusion of the expanded styrene.